/*
    KmPlot - a math. function plotter for the KDE-Desktop

    SPDX-FileCopyrightText: 2004 Fredrik Edemar <f_edemar@linux.se>
    SPDX-FileCopyrightText: 2006 David Saxton <david@bluehaze.org>

    This file is part of the KDE Project.
    KmPlot is part of the KDE-EDU Project.

    SPDX-License-Identifier: GPL-2.0-or-later

*/

#include "kparametereditor.h"

#include <QDebug>
#include <QDialogButtonBox>
#include <QFile>
#include <QFileDialog>
#include <QListWidget>
#include <QPushButton>
#include <QTemporaryFile>
#include <QTextStream>
#include <QVBoxLayout>

#include <KConfigGroup>
#include <KIO/StoredTransferJob>
#include <KJobWidgets>
#include <KMessageBox>

#include "maindlg.h"

#include <assert.h>

class ParameterValueList;

KParameterEditor::KParameterEditor(QList<Value> *l, QWidget *parent)
    : QDialog(parent)
    , m_parameter(l)
{
    m_mainWidget = new QParameterEditor(this);
    setWindowTitle(i18nc("@title:window", "Parameter Editor"));
    QVBoxLayout *mainLayout = new QVBoxLayout;
    setLayout(mainLayout);
    mainLayout->addWidget(m_mainWidget);

    QDialogButtonBox *buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
    QPushButton *okButton = buttonBox->button(QDialogButtonBox::Ok);
    okButton->setDefault(true);
    okButton->setShortcut(Qt::CTRL | Qt::Key_Return);
    connect(buttonBox, &QDialogButtonBox::accepted, this, &KParameterEditor::accept);
    connect(buttonBox, &QDialogButtonBox::rejected, this, &KParameterEditor::reject);
    mainLayout->addWidget(buttonBox);

    mainLayout->setContentsMargins(0, 0, 0, 0);

    m_mainWidget->cmdNew->setIcon(QIcon::fromTheme("document-new"));
    m_mainWidget->cmdDelete->setIcon(QIcon::fromTheme("edit-delete"));
    m_mainWidget->moveUp->setIcon(QIcon::fromTheme("go-up"));
    m_mainWidget->moveDown->setIcon(QIcon::fromTheme("go-down"));
    m_mainWidget->cmdImport->setIcon(QIcon::fromTheme("document-open"));
    m_mainWidget->cmdExport->setIcon(QIcon::fromTheme("document-save"));

    m_mainWidget->list->setFocusPolicy(Qt::NoFocus);

    connect(m_mainWidget->value, &EquationEdit::upPressed, this, &KParameterEditor::prev);
    connect(m_mainWidget->value, &EquationEdit::downPressed, this, &KParameterEditor::next);

    for (const Value &v : qAsConst(*m_parameter))
        m_mainWidget->list->addItem(v.expression());

    connect(m_mainWidget->cmdNew, &QPushButton::clicked, this, &KParameterEditor::cmdNew_clicked);
    connect(m_mainWidget->cmdDelete, &QPushButton::clicked, this, &KParameterEditor::cmdDelete_clicked);
    connect(m_mainWidget->moveUp, &QPushButton::clicked, this, &KParameterEditor::moveUp);
    connect(m_mainWidget->moveDown, &QPushButton::clicked, this, &KParameterEditor::moveDown);
    connect(m_mainWidget->cmdImport, &QPushButton::clicked, this, &KParameterEditor::cmdImport_clicked);
    connect(m_mainWidget->cmdExport, &QPushButton::clicked, this, &KParameterEditor::cmdExport_clicked);
    connect(m_mainWidget->list, &QListWidget::currentItemChanged, this, &KParameterEditor::selectedConstantChanged);

    connect(m_mainWidget->value, &EquationEdit::textEdited, this, &KParameterEditor::saveCurrentValue);
    connect(m_mainWidget->value, &EquationEdit::textChanged, this, &KParameterEditor::checkValueValid);
    connect(m_mainWidget->value, &EquationEdit::returnPressed, m_mainWidget->cmdNew, &QAbstractButton::click);

    checkValueValid();

    m_mainWidget->value->setFocus();
}

KParameterEditor::~KParameterEditor()
{
}

void KParameterEditor::accept()
{
    qDebug() << "saving\n";
    m_parameter->clear();
    QString item_text;
    for (int i = 0; i < m_mainWidget->list->count(); i++) {
        item_text = m_mainWidget->list->item(i)->text();
        if (!item_text.isEmpty()) {
            Value value;
            if (value.updateExpression(item_text))
                m_parameter->append(value);
        }
    }

    QDialog::accept();
}

void KParameterEditor::moveUp()
{
    int current = m_mainWidget->list->currentRow();

    if (current == 0)
        return;

    QListWidgetItem *item = m_mainWidget->list->takeItem(current - 1);
    m_mainWidget->list->insertItem(current, item);
}

void KParameterEditor::moveDown()
{
    int current = m_mainWidget->list->currentRow();

    if (current == m_mainWidget->list->count() - 1)
        return;

    QListWidgetItem *item = m_mainWidget->list->takeItem(current + 1);
    m_mainWidget->list->insertItem(current, item);
}

void KParameterEditor::cmdNew_clicked()
{
    QListWidgetItem *item = new QListWidgetItem(m_mainWidget->list);
    item->setText("0");
    m_mainWidget->list->setCurrentItem(item);
    m_mainWidget->value->setFocus();
    m_mainWidget->value->selectAll();
}

void KParameterEditor::prev()
{
    int current = m_mainWidget->list->currentRow();
    if (current > 0)
        m_mainWidget->list->setCurrentRow(current - 1);
}

void KParameterEditor::next()
{
    int current = m_mainWidget->list->currentRow();
    if (current < m_mainWidget->list->count() - 1)
        m_mainWidget->list->setCurrentRow(current + 1);
    else
        cmdNew_clicked();
}

void KParameterEditor::selectedConstantChanged(QListWidgetItem *current)
{
    m_mainWidget->cmdDelete->setEnabled(current != 0);
    m_mainWidget->value->setText(current ? current->text() : QString());
    m_mainWidget->value->selectAll();
}

void KParameterEditor::cmdDelete_clicked()
{
    QListWidgetItem *item = m_mainWidget->list->currentItem();
    if (!item)
        return;

    m_mainWidget->value->clear();
    m_mainWidget->list->takeItem(m_mainWidget->list->currentRow());
    delete item;

    m_mainWidget->cmdDelete->setEnabled(m_mainWidget->list->currentItem() != 0);
}

void KParameterEditor::saveCurrentValue()
{
    QListWidgetItem *current = m_mainWidget->list->currentItem();
    if (!current)
        current = new QListWidgetItem(m_mainWidget->list);

    current->setText(m_mainWidget->value->text());
    m_mainWidget->list->setCurrentItem(current);
}

bool KParameterEditor::checkValueValid()
{
    QString valueText = m_mainWidget->value->text();
    Parser::Error error;
    (double)XParser::self()->eval(valueText, &error);
    bool valid = (error == Parser::ParseSuccess);
    m_mainWidget->valueInvalidLabel->setVisible(!valueText.isEmpty() && !valid);
    return valid;
}

void KParameterEditor::cmdImport_clicked()
{
    QUrl url = QFileDialog::getOpenFileUrl(this, i18n("Open Parameter File"), QUrl(), i18n("Plain Text File (*.txt)"));
    if (url.isEmpty())
        return;

    if (!MainDlg::fileExists(url)) {
        KMessageBox::sorry(0, i18n("The file does not exist."));
        return;
    }

    bool verbose = false;
    QFile file;
    if (!url.isLocalFile()) {
        KIO::StoredTransferJob *transferjob = KIO::storedGet(url);
        KJobWidgets::setWindow(transferjob, 0);
        if (!transferjob->exec()) {
            KMessageBox::sorry(0, i18n("An error appeared when opening this file: %1", transferjob->errorString()));
            return;
        }
        QTemporaryFile tmpfile;
        tmpfile.setAutoRemove(false);
        tmpfile.open();
        tmpfile.write(transferjob->data());
        file.setFileName(tmpfile.fileName());
        tmpfile.close();
    } else
        file.setFileName(url.toLocalFile());

    if (file.open(QIODevice::ReadOnly)) {
        QTextStream stream(&file);
        QString line;
        for (int i = 1; !stream.atEnd(); i++) {
            line = stream.readLine();
            if (line.isEmpty())
                continue;

            Parser::Error error;
            XParser::self()->eval(line, &error);
            if (error == Parser::ParseSuccess) {
                if (!checkTwoOfIt(line)) {
                    m_mainWidget->list->addItem(line);
                }
            } else if (!verbose) {
                if (KMessageBox::warningContinueCancel(
                        this,
                        i18n("Line %1 is not a valid parameter value and will therefore not be included. Do you want to continue?", i))
                    == KMessageBox::Cancel) {
                    file.close();
                    QFile::remove(file.fileName());
                    return;
                } else if (KMessageBox::warningYesNo(this,
                                                     i18n("Would you like to be informed about other lines that cannot be read?"),
                                                     QString(),
                                                     KGuiItem(i18n("Get Informed")),
                                                     KGuiItem(i18n("Ignore Information")))
                           == KMessageBox::No)
                    verbose = true;
            }
        }
        file.close();
    } else
        KMessageBox::sorry(0, i18n("An error appeared when opening this file"));

    if (!url.isLocalFile())
        QFile::remove(file.fileName());
}

void KParameterEditor::cmdExport_clicked()
{
    if (!m_mainWidget->list->count())
        return;
    QUrl url = QFileDialog::getSaveFileUrl(this, i18n("Save File"), QUrl(), i18n("Plain Text File (*.txt)"));
    if (url.isEmpty())
        return;

    if (!MainDlg::fileExists(url)
        || KMessageBox::warningContinueCancel(
               this,
               i18n("A file named \"%1\" already exists. Are you sure you want to continue and overwrite this file?", url.toDisplayString()),
               i18n("Overwrite File?"),
               KStandardGuiItem::overwrite())
            == KMessageBox::Continue) {
        if (!url.isLocalFile()) {
            QTemporaryFile tmpfile;

            if (tmpfile.open()) {
                QTextStream stream(&tmpfile);
                for (int i = 0; i < m_mainWidget->list->count(); i++) {
                    QListWidgetItem *it = m_mainWidget->list->item(i);
                    stream << it->text();
                    if (i < m_mainWidget->list->count() - 1)
                        stream << '\n'; // only write a new line if there are more text
                }
                stream.flush();
            } else
                KMessageBox::sorry(0, i18n("An error appeared when saving this file"));

            Q_CONSTEXPR int permission = -1;
            QFile file(tmpfile.fileName());
            file.open(QIODevice::ReadOnly);
            KIO::StoredTransferJob *putjob = KIO::storedPut(file.readAll(), url, permission, KIO::JobFlag::Overwrite);
            if (!putjob->exec()) {
                KMessageBox::sorry(0, i18n("An error appeared when saving this file"));
                return;
            }
            file.close();
        } else {
            QFile file;
            qDebug() << "url.path()=" << url.toLocalFile();
            file.setFileName(url.toLocalFile());
            if (file.open(QIODevice::WriteOnly)) {
                QTextStream stream(&file);
                for (int i = 0; i < m_mainWidget->list->count(); i++) {
                    QListWidgetItem *it = m_mainWidget->list->item(i);
                    stream << it->text();
                    if (i < m_mainWidget->list->count() - 1)
                        stream << '\n'; // only write a new line if there are more text
                }
                file.close();
            } else
                KMessageBox::sorry(0, i18n("An error appeared when saving this file"));
        }
    }
}

bool KParameterEditor::checkTwoOfIt(const QString &text)
{
    return !m_mainWidget->list->findItems(text, Qt::MatchExactly).isEmpty();
}
